Pierre Goffette

Yttrium-90 TOF PET scan demonstrates high-resolution biodistribution after liver SIRT

The decay of Y has a minor branch to the 0 excited state [1], followed by an internal ee creation which happens in 32 out of one million decays [2]. Consequently, Y PET scan was proposed in order to assess the biodistribution [3] of Y-labelled therapeutic agents. A 61-year-old woman was referred for treatment of chemorefractory colorectal liver metastasis. Based on the pretreatment evaluation (including a diagnostic FDG PET/CT scan on day 1, and a prophylactic embolization of the right gastric and gastroduodenal arteries followed by a Tc-MAA SPECT/CT scan on day 8), 1.3 GBq of Y-labelled SIR-Spheres were administered by sequential catheterization of both liver lobes (day 15). Subsequently, a 30-min Y TOF PET/CT scan was performed using a Philips GEMINI TF camera. In order to prevent saturation of the detectors, a copper ring of 2.5 mm thickness was inserted into the gantry to absorb the bremsstrahlung x-rays. The TOF data were reconstructed with attenuation and scatter correction using Philips RAMLA software (eight iterations, three subsets). An additional 20 min bremsstrahlung Y-SPECT was acquired using a Trionix XLT20 triple head camera (medium energy collimator, 30% window centred on 90 keV). Data were reconstructed using OSEM (four iterations, six subsets). As illustrated, despite the differences in their respective uptake mechanism, Y-PET better reflects the tumour heterogeneity assessed by FDG PET/CT (a necrotic core surrounded by active tumour margins) than traditional bremsstrahlung Y-SPECT. This gain in resolution should therefore contribute to increasing the accuracy of the dose distribution into the tumours and their surrounding healthy tissues.

Feasibility of 90Y TOF PET-based dosimetry in liver metastasis therapy using SIR-Spheres

Purpose90Y-labelled compounds used in targeted radiotherapy are usually imaged with SPECT by recording the bremsstrahlung X-rays of the β decay. The continuous shape of the X-ray spectrum induces the presence of a significant fraction of scatter rays in the acquisition energy window, reducing the accuracy of biodistribution and of dosimetry assessments.MethodsThe aim of this paper is to use instead the low branch of e− e+ pair production in the 90Y decay. After administration of 90Y-labelled SIR-Spheres by catheterization of both liver lobes, the activity distribution is obtained by 90Y time-of-flight (TOF) PET imaging. The activity distribution is convolved with a dose irradiation kernel in order to derive the regional dosimetry distribution.ResultsEvaluation on an anatomical phantom showed that the method provided an accurate dosimetry assessment. Preliminary results on a patient demonstrated a high-resolution absorbed dose distribution with a clear correlation with tumour response.ConclusionThis supports the implementation of 90Y PET in selective internal radiation therapy of the liver.

Alpha-fetoprotein and modified response evaluation criteria in Solid Tumors progression after locoregional therapy as predictors of hepatocellular cancer recurrence and death after transplantation.

Locoregional therapy (LRT) is being increasingly used for the management of hepatocellular cancer (HCC) in patients listed for liver transplantation (LT). Although several selection criteria have been developed, stratifications of survival according to the pathology of explanted livers and pre‐LT LRT are lacking. Radiological progression according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) and alpha‐fetoprotein (AFP) behavior was reviewed for 306 patients within the Milan criteria (MC‐IN) and 116 patients outside the Milan criteria (MC‐OUT) who underwent LRT and LT between January 1999 and March 2010. A prospectively collected database originating from 6 collaborating European centers was used for the study. Sixty‐one patients (14.5%) developed HCC recurrence. For both MC‐IN and MC‐OUT patients, an AFP slope > 15 ng/mL/month and mRECIST progression were unique independent risk factors for HCC recurrence and patient death. When the radiological Milan criteria (MC) status was combined with radiological and biological progression, MC‐IN and MC‐OUT patients without risk factors had similarly excellent 5‐year tumor‐free and patient survival rates. MC‐IN patients with at least 1 risk factor had worse outcomes, and MC‐OUT patients with at least 1 risk factor had the poorest survival (P < 0.001). In conclusion, both radiological and biological modifications permit documentation of the response to LRT in patients waiting for LT. According to these 2 parameters, tumor progression significantly increases the risk of recurrence and patient death not only for MC‐OUT patients but also for MC‐IN patients. The monitoring of both parameters in combination with the initial radiological MC status is an essential element for further refining the selection criteria for potential liver recipients with HCC. Liver Transpl 19:1108‐1118, 2013.

The place of liver transplantation in Caroli's disease and syndrome

Carolis disease (CD) or syndrome (CS) are rare inherited disorders which may cause severe, life‐threatening, cholangitis or which may lead to hepatobiliary degeneration. The typical cystic biliary anomalies are often associated to congenital hepatic fibrosis (CHF) and, less frequently, to cystic renal disease especially autosomic recessive polycystic kidney disease (ARPKD). The place of liver transplantation (LT) in the treatment of CD or CS is evaluated based on our own experience of three successfully transplanted patients, the literature review of 19 patients and the European experience with 110 patients collected in the European Liver Transplant Registry. LT should be proposed as a definitive therapeutic option once severe cholangitis or (suspicion of) malignant transformation is present. The frequently used radiological, endoscopical or surgical biliary drainage procedures carry a high morbidity and mortality rate. In case of concomitant symptomatic CHF and renal failure, combined or sequential hepatorenal transplantation should be carried out, dependant on the evolution of the hepatic and renal disease. In case of associated ARPKD, renal transplantation is often indicated early on because of the more rapid progression of the renal component of the disease.

Gadolinium dimeglumine: an alternative contrast agent for digital subtraction angiography.

Abstract. The aim of this study was to evaluate gadolinium diethylenetriaminepenta-acetic acid (Gd-DTPA) as an alternative contrast agent for digital subtraction angiography (DSA) in patients with renal insufficiency or previous anaphylactic reaction to iodinated contrast agents. We performed 34 DSAs in 31 patients by use of the commercially available 0.5-M Gd-DTPA solution (Magnevist, Schering, Berlin, Germany). The contrast material was power- or hand-injected at the same rate as iodinated contrast material, without exceeding a total amount of 0.4 mmol/kg body weight. In 18 studies Gd-DTPA was the sole contrast agent. In 9 cases gadolinium injections were combined with carbon dioxide. Restricted non-ionic contrast medium injections were administered to complete the examinations in 7 cases and for comparative purposes in 1 case. Cerebral and carotid arteries, one superior limb, abdominal aorta, renal arteries, renal transplants, iliac arteries and inferior limbs were imaged, and ten endovascular interventional procedures, including three transjugular intrahepatic percutaneous stent shunts, were performed. No side effects were observed. Diagnostic angiographic images were obtained in all cases except in 5 of the 8 distal run-off studies. Gadolinium-based contrast can produce clinically useful angiograms in patients with a contra-indication to iodine who must undergo angiography.

Surgical clipping may lead to better results than coil embolization: results from a series of 101 consecutive unruptured intracranial aneurysms.

OBJECTIVERecent reports in the literature have described a significant discrepancy in adverse outcomes between coil embolization (CE; 10%) and surgical clipping (SC; 25%) for the management of unruptured intracranial aneurysms (UIA). This discrepancy led us to analyze our experience. METHODSIn 1996, we designed a prospective study of patients with UIA in which CE was considered the treatment of choice and was performed if the interventional neuroradiologists deemed the aneurysm’s fundus-to-neck ratio accessible for CE. SC was performed only if complete CE was unlikely to be achieved or in patients in whom CE already had failed. RESULTSCE was performed in 38 patients with at least one UIA (41 UIAs, 83% in the anterior circulation). SC was performed in 39 patients with at least one UIA unsuitable for CE (59 UIAs, including 6 after failed CE, 96.5% in the anterior circulation). For CE, the total obliteration rate was 56.1%, the subtotal was 14.6%, and CE failed in 29.3%. There were transient complications in 10% of the cases and permanent complications in 7.5%. Of the 12 failed CE procedures, 7 (58%) were performed for middle cerebral artery aneurysms. For SC, the total obliteration rate was 93.2%, the subtotal was 1.7%, and SC failed (wrapping) in 5.1%. There were transient complications in 16.3% of the patients and permanent complications in 1.7%. The success rate for CE was similar to that for SC only when CE was used for aneurysms with a fundus-to-neck ratio of at least 2.5. CONCLUSIONSC can produce better results than CE in patients with UIA of the anterior circulation. CE as a first-line treatment should be reserved for patients with UIAs with a fundus-to-neck ratio of 2.5 or greater.

Traumatic injuries: imaging and intervention in post-traumatic complications (delayed intervention)

Abstract. The nonoperative management (NOM) of abdominal trauma has gained increasing acceptance over the past decade. This approach has been extended to severe trauma patients previously considered as candidates for surgery. Consequently, the incidence of delayed and uncommonly encountered complications has increased. Causes of delayed complications are multiple and include: (a) abnormal or insufficient injury healing process; (b) retention of necrotic tissue; (c) secondary infection of initially sterile collections; and (d) underestimation of injury severity. The purpose of this review article is to explain the role of various imaging modalities in detecting post-traumatic delayed complications and to highlight the usefulness of minimally invasive techniques, including laparoscopy, biliary endoscopy, therapeutic angiography and image-guided drainage. Subsequent complications, which do not necessarily negatively influence the final outcome, are often predictable, virtually obligatory consequences of the successful NOM of high-grade or complex abdominal injuries. Between 50 and 60% of those patients with grade-IV or grade-V liver or splenic lacerations require some type of interventional treatment; therefore, indiscriminate discharge of patients with solid organ injury managed conservatively may be potentially harmful. As the incidence of complications is higher for more severe grade-IV or grade-V liver, spleen, or kidney injuries, scheduled follow-up CT scans may be rational in this subset of patients to identify potential complications amenable to early application of interventional techniques. Follow-up CT scans are unnecessary in stable adults or children with low-grade injury. Delayed splenic or hepatic rupture is one of the major concerns because this type of complication remains difficult to predict and historically often requires emergent surgery. These ruptures may benefit from NOM, should the same criteria as for primary rupture be respected. Conversely, parenchymatous focal pooling of contrast on initial CT is a good predictor for the development of delayed vascular malformation. In children, as a large part of splenic and hepatic vascular malformations resolve spontaneously, expectant observation may be indicated provided that a strict imaging follow-up is performed until complete disappearance of these lesions. If needed, embolization of parenchymal vascular lesions should be performed as selectively as possible in order to avoid functional parenchyma loss and to reduce the risk of secondary infection of hematoma or ischemic tissue. Technical improvements, such as microcatheter systems and direct percutaneous approach to targeted lesions, have widened the potential for safe endovascular management of acquired vascular malformations. Advantages and disadvantages relative to the different embolic agents are explained. Endoscopic retrograde pancreatography is the chief investigational tool for detecting biliary and pancreatic ducts injuries. The respective roles of endoscopic, percutaneous and surgical approaches in the management of these complications are discussed. The CT scan and ultrasound-guided drainage provide effective nonoperative options in the management of post-traumatic parenchymatous and (retro)-peritoneal collections. Treatment modalities of less common complications, such as bowel stricture or perforation, mesenteric vascular injuries and renal trauma-induced hypertension, are reviewed.

Acute intestinal ischemia due to occlusion of the superior mesenteric artery: detection with Doppler sonography.

The aim of our study was to assess the feasibility of using Doppler sonography for the detection of acute intestinal ischemia due to occlusion of the superior mesenteric artery. Between September 1993 and March 1995, abdominal sonography with Doppler imaging of the mesenteric vessels was performed in 770 patients with emergency admissions for acute abdominal pain. In six cases, the diagnosis, based on surgery or arteriography and computed tomography, was acute intestinal ischemia due to complete or localized occlusion of the superior mesenteric artery. Five cases of occlusion of the superior mesenteric artery were correctly detected by Doppler sonography. These results suggest that Doppler sonography may be a feasible method for detecting acute intestinal ischemia due to proximal superior mesenteric artery occlusion.

Liver transplantation and neuroendocrine tumors: lessons from a single centre experience and from the literature review.

Neuroendocrine tumor (NET) metastases represent at this moment the only accepted indication of liver transplantation (LT) for liver secondaries. Between 1984–2007, nine (1.1%) of 824 adult LTs were performed because of NET. There were five well differentiated functioning NETs (four carcinoids and one gastrinoma), three well differentiated non functioning NETs and one poorly differentiated NET. Indications for LT were an invalidating unresectable tumor (4×), and/or a diffuse tumor localization (3×) and/or a refractory hormonal syndrome (5×). Median post‐LT patient survival is 60.9 months (range 4.8–119). One‐, 3‐ and 5‐year actuarial survival rates are 88%, 77% and 33%; 1, 3 and 5 years disease free survival rates are 67%, 33% and 11%. Due to a more rigorous selection procedure, results improved since 2000; three out of five patients are alive disease‐free at 78, 84 and 96 months. Review of these series together with a review of the literature reveals that results of LT for this oncological condition can be improved using better selection criteria, adapted immunosuppression and neo‐ and adjuvant surgical as well as medical tretament. LT should be considered earlier in the therapeutic algorithm of selected NET patients as it is the only therapy that can offer a cure.

Transjugular intrahepatic portosystemic shunt after adult liver transplantation: experience in eight patients.

BACKGROUND Transjugular intrahepatic portosystemic shunting (TIPS) has become an effective treatment for the complications of portal hypertension. We assessed the feasibility and outcome of TIPS in liver transplant recipients. METHODS During the period from December 1992 to January 1998, eight adults presenting recurrent hepatitis C virus (five patients) and hepatitis B virus (one patient) infection, veno-occlusive disease (one patient), and secondary biliary cirrhosis (one patient) had TIPS because of refractory ascites (five patients), bleeding esophageal varices (one patient), refractory hepatic hydrothorax (one patient), retransplantation (two patients), and redo-biliary surgery (one patient). RESULTS In two patients, the procedure was difficult due to cavo-caval implantation. Ascites, hydrothorax, and variceal bleeding were controlled in all patients. Moderate to severe encephalopathy developed in four patients; two patients had worsening of their existing encephalopathy. Three of five patients treated with cyclosporine needed a drastic dose reduction due to the development of severe side effects. No long-term survivor developed shunt stenosis or occlusion. Two patients did moderately well at 6 and 14 months, respectively; the former died due to chronic rejection while waiting for a retransplantation. Three did well at 14, 36, and 28 months, respectively; the latter patient died of liver failure 32 months after TIPS. One jaundiced patient died after 1.5 months due to necrotic pancreatitis. Two patients died after 4 and 8.5 months, respectively, due to liver failure; the latter was doing well until 7 months after TIPS. CONCLUSIONS TIPS is feasible in transplant recipients in cases of decompensated allograft cirrhosis, of allograft veno-occlusive disease or when retransplantation or redo-biliary surgery are scheduled in the presence of portal hypertension. At transplantation, the surgeon should keep in mind the eventuality of a later TIPS procedure. Close immunosuppression monitoring is warranted because modified metabolization of cyclosporine (and probably tacrolimus) may cause serious side effects.